Defection needs better tile generation and AI pathing improvements

[Lokidus_Prime]

Against our better judgement, a friend and I decided to tackle a Defection Arbitration mission on the Grineer Asteroid tileset.  Once the defectors started spawning at point B, some defectors would end up going a way where they would just be stuck running into a wall, trying to run an alternate path that simply didn't exist.  The spot where the defectors would get stuck in had a dead-end pipe on the other side of the wall - presumably where these 2 rooms were trying to connect but couldn't properly do so (the waypoint was trying to lead us to go this way too).  As neither of us had any frames that could teleport them, we had no choice but to let defectors from 3 squads die before we were able to unlock extraction.  The first squad had 2 that went the bugged way, the 2nd squad all 4 had to die, and the 3rd squad only had one.  This mode really needs some adjustments to fix issues like this, because the AI pathing the biggest problem with this mode.  The infested corpus ship has issues too, as the defectors can easily get stuck on some of the terrain there, although most of the time they eventually teleport out of it if they do.